The invention relates to an error-correcting method for the transmission of word-wise organised data, comprising the following steps:
a. receiving a first number of data words in a first error encoder in order to add thereto a first series of check words on the basis of a first generator matrix of a first error-correcting code;
b. using delays which are all mutually different within each first number of data words and the associated first series of check words, interleaving sid first number of data words and said first series of check words among as many second numbers of words, said delays in sequence increasing by an interleaving increment;
c. receiving a second number of words in a second error encoder in order to add thereto a second series of check words on the basis of a second generator matrix of a second error-correcting code, thus forming a third number of words so that successive third numbers of words can be successively applied to a medium for transmission;
d. reproducing and, if possible and necessary, correcting reproducing of said second numbers of words after the transmission on the basis of the second parity check matrix associated with the second generator matrix;
e. reproducing and, if possible and necessary, correctively reproducing said first numbers of input words for supply to a user by the de-interleaving of said second numbers of words and on the basis of the first parity check matrix associated with the first generator matrix. A method of this kind is known from the previous Netherlands Patent Application 8102441 (PHQ 80.009) in the name of Applicant which is based on a Japanese Application 567608-80 by Sony Corporation, Shinagawa-ku, Tokyo, Japan. These correspond to U.S. Pat. No. 4,413,340. Instead of "word", the term "symbol" is also customarily used. Within each second number of words or within each third number of words, a limited number of words can be corrected or another number of words can be detected as being incorrect, said limited numbers being given by the minimum Hamming distance taken over the words. In this respect reference is also made to the previous Netherlands Patent Application 8200207 (PHN 10 242) in the name of Applicant which is incorporated herein by way of reference. The known method is especially intended for use in the digital recording of acoustic signals for HIFI reproduction. In given, rather exceptional cases the described error correction is not quite adequate. If no further steps were taken, an incorrect word would be converted into an audio signal which could cause a clock-like noise of arbitrary amplitude. In order to counteract this phenomenon, it has been proposed for audio applications to produce the audio signal in a different way when a non-correctable error is detected, for example by repeating the preceding audio signal (zero order interpolation), by muting the incorrect audio signal or by treating it in such a way that the disturbance is not at all or only hardly noticed by a listener. It is also possible to use a data transmission method of the described kind for non-audio information, such as text characters, computer data, programs for video games, and the like. For such applications it is important to supply the user only with data which has been found to be correct, if possible.